Flavobacterium anseongense sp. nov. and Flavobacterium wongokense sp. nov., isolated from freshwater and freshwater soil in South Korea

Two novel, non-motile, Gram-stain-negative, rod-shaped bacterial strains, designated AS60^T and WG47^T, were isolated from freshwater in South Korea. To clarify their taxonomic positions, both strains were characterized based on genomic information, including 16S rRNA gene and draft genome sequences. Phylogenetic analyses revealed that both isolates belong to the genus <i>Flavobacterium</i>. Based on 16S rRNA gene sequencing, AS60^T clustered with <i>Flavobacterium silvisoli</i> KACC 21178^T (96.09%), <i>Flavobacterium cheonhonense</i> KACC 14967^T (96.07%) and <i>Flavobacterium sangjuense</i> KACC 17473^T (95.96%). Strain WG47^T showed the highest similarity to <i>Flavobacterium dankookense</i> KACC 23179^T (97.14%), <i>F. cheonhonense</i> KACC 14967^T (97.07%) and <i>Flavobacterium chungnamense</i> KACC 14971^T (96.71%). The draft genomes of AS60^T and WG47^T were 3.07 and 3.30 Mb, with G+C contents of 35.6 and 38.9 mol%, respectively. Average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) values were calculated. For AS60^T, ANI values compared to <i>F. silvisoli</i> KACC 21178^T, <i>F. cheonhonense</i> KACC 14967^T and WG47^T were 76.67, 79.38 and 76.01%, respectively, with dDDH values of 20, 19.6 and 22.1%. For WG47^T, ANI values compared to <i>F. dankookense</i> KACC 23179^T and <i>F. cheonhonense</i> KACC 14967^T were 75.12 and 74.75%, with dDDH values of 19.9 and 19.2%. Both strains exhibited MK-6 as the predominant respiratory quinone, and their fatty acid profiles included iso-C_15:1, iso-C_15:0 3OH, iso-C_15:1 G, iso-C_16:0, iso-C_16:0 3OH and iso-C_17:0 3OH. Phosphatidylethanolamine was the major polar lipid. Strain WG47^T was found to produce flexirubin-type pigments, while AS60^T did not. These results, combined with phenotypic and biochemical data, suggest that strains AS60^T and WG47^T represent two novel species of <i>Flavobacterium</i>, for which the names <i>Flavobacterium anseongense</i> sp. nov. (AS60^T=KACC 22413^T=LMG 32491^T) and <i>Flavobacterium wongokense</i> sp. nov. (WG47^T=KACC 22407^T=LMG 32500^T) are proposed.